1. Field of the Invention
The present invention relates to an optical apparatus having a function for testing shake compensation by using external communication and, more particularly, to an optical apparatus capable of image blurring correction, such as a camera for detecting a camera shake, and driving a correction optical member inserted in the optical path of a photographing optical system on the basis of the detection value to reduce the influence of image blurring which is caused during a film exposure operation.
2. Description of the Related Art
Various techniques for image blurring correction optical systems used for optical apparatuses such as cameras have been proposed. For example, in the prior art shown in FIG. 22, a parallel glass 302 is arranged on the image plane side of a photographing lens 301, and any blurring of an image on a film surface 303 is corrected by inclining the parallel glass 302 in accordance with the blurring amount of the image.
In the prior art shown in FIG. 23, a variable vertical angle prism 304 constituted by two types of elastic members 304a and 304b is arranged on the object side of a photographing lens 301, and the vertical angle of the prism 304 is changed by actuators 305a and 305b in accordance with the total shake amount of the photographing optical system, thereby correcting the blurring of an image on an imaging plane 303.
In addition, a technique of correcting image blurring by moving part of a photographing lens system in accordance with the shake amount is also known.
A technique associated with a camera having an operation mode of checking an image blurring correction function is disclosed in Jpn. Pat. Appln. KOKAI Publication No. 4-361240. In this camera, the operation of the image blurring correction function can be arbitrarily checked by operating a predetermined switch.
According to the technique disclosed in Jpn. Pat. Appln. KOKAI Publication No. 4-361240, however, even if the image blurring correction function is used, the user can only determine through the viewfinder that "the image blurring correction function is ON". In this prior art, therefore, the operation of the image blurring correction function cannot be quantitatively evaluated, and the user can only determine whether the function is working or not.